Furnace for burning liquid fuel.



PATENTE'D NOV. 20,1906.

v B'. H. PEABODY- v FURNACE 1- 011 BURNING LIQUID'FUEL.

APPLIGATION FILED AUGJS. 1904.

222M @(1 anew: omimomn W w ERNEST P'EABODY, on NEW roan,

FURNACE FOR BURNENG LlQUlD FUEL.

Specification of Letters Patent.

Patented Nov. 20, me

Application filed August 15. 1904. Serial No: 220,785.

To all whom; "it may concern:

Belt known that I, ERNEST H. PEABODY, a citizen of the Umted States, anda resldent of New York city, borough of Manhattan, in v the county andState of New York, have invented a new and useful Improvement inFurnaces for Burning Liquid Fuel, of which the following is aspecification. l

T his invention relates to furnaces for burning atomized liquid fuel;and it consists in certain novel structures and devices especiallyadapted therefor which are pointed out in the claims concluding thisspecification.

The various methods of burning fuel may be divided into three.,distinotclasses first,

that in which thefuelywhether solid or liquid, is stationary; second,that in which the fuel is introduced in the form of a gas or is sofinely subdivided that it burns like a gas with flameless combustion,and, third, that in which the liquid fuel is introduced in the form ofspray and burns with flame. My

present invention relates to the last-named method. The practical art ofburning such sprayed fuel differs radically from and in volves problemsnot present in the art of burning stationary fuel (whether liquid orsolid) or the art of burning gas or oil atom ized to such a degree as toproduce, like gas, fiameless combustion. This difference is due to thefact, among other things, that when stationary fuel is used the fuel iswidely distributed and at rest on the grate-bars, and the products ofcombustion. are controlled by "the furnace-draft alone and that when gasis, used or flameless combustionotherwise produced questions of momentumand slow combustion do not enter into the problem. When, onthe-contrary, sprayed liquid fuel is used, the combustion is slow andthe distribution of the products of combustion is controlled not by thefurnace-draft alone, but also and mainly by the direction and momentumof the injected moving fuel and its great expansion when passing fromthe liquid .to the gaseous condition. Furthermore, in the case ofsprayed liquid fuel energy is nec essarily consumed in subdividing itand injecting it into the furnace, and to diminish the energy thusconsumed is a matter of prime importance. For those reasons, amongothers, furnaces which are well adapted, when using stationary orgaseous fuel to distribute the hot gases uniformly over and throughoutthe body of the water-tubes cannot be effectively used with sprayedliquid fuel burned with flame, particularly when operated at highcapacities, for the reason that the heated gases concentrate on certainportions of the tubes, quickly burning them out and resulting in otherlosses. 1 Thisdifficulty l have sought to overcome by the use of certainforms of bridge-walls and baffleplates; but these devices have provedinadequate. When, however, constructed as hereinafter described, theboiler may be highly forced without local overheating of the exposedtube-surfaces. No baflie or target wall is required. The flame isthoroughly distributed through the furnace, the gases eX. pand and burnwith substantial'coinpleteness before being cooled by the boiler-tubesbelow the temperature of ignition, and the amount of steam for atomizingthe oil'may be reduced to the minimum, thus giving greatly-improved netresults in evaporation of water per pound of oil after deducting thepercentage of steam used in atomizing.

Oils of the lighter varieties, such as the Texas, Ohio, and Pennsylvaniaoils, running in specific gravity from 22Baum up, can be gasified oratomized to the point of giving nameless combustion without the use ofavery excessive amount of steam or other atomiz ing medium in theburners. Under these conditions the oil is easily handled, and the formof the furnace is comparatively of slight importance. On the contrary,heavy residuums and the heavy natural oils of Calil'ornia, running aslow as 12 or 14 Baum cannot be gasilied or atomized fine enough to giveflameless combustion without using so much of the gasifying or atomizingagent as to make this method of handling so expensive as to beprohibitive. Such oil is there fore when sprayed into the furnace burnedwith a considerable quantity of flame, and in order to obtain maximumefficiency and to insure high capacity without injury to the generatorthe form of the furnace and method of admitting the oil and distributingthe resulting flame throughout the furnace is of vital importance.Moreover, if the furnace is constructed so as to economically and safelyhandle a large amount of flame the quantity of steam used for atomizingthe oil can be reduced to a minimum, thus produc:

ing a direct'saving in. the cost of atomizing.

too

It has been found, further, that a'furnace which is adapted for handlingheavy oils with considerable flame s also more economical n the use oflight o1ls,wh1ch can also In the drawings, which form a part of thisspecification, Figure l-represents a side view of a steam-generator ofthe type referred to and shows the relative arrangements of the vpartsfor using liquid fuelin its furnacechamber in accordance with myinvention.-

' Fig. 2 is a plan view of the base or floor of the chamber, showin therelative position and means for admittlng the constituents of the fuel.'to the chamber. Fig. 3 is an enlarged view, partly in section, of thespecific details of; construction of the base of the chamber and theconnected fuel-feeding devices and supports. Fig. 4 is a transversesection of Fig. 3 on the line 4.

The following is a description of the structure shown in theaccompanying drawings, Which illustrate my invention, applied in theform at present preferred by me; but it will "be understood that variousmodifications and changes may be; made therein without departing fromthe spirit of my invention and without exceeding the scope of my claims.

The main parts of the steam-generator shown consist of the furnace-space1, the group of inclined water-tubes 2, which are connected to headers3, that communicate with the elevated steam and water drum 4 by means ofthe do'wnflow -pipes 5 at the rear S to the chamber.

and the riser-pipes or ni ples 6 at the front. A bridge-wall 7 isprovided forming the rear end. of the furnace-chamber. A roof 8 isprovided, covering the smalleror' lower end of the bridge-wall 7, andbaffles or partitions'g are placed transversely of the group of tubes'to direct the products of combustion to cross and recross the tubes tothe uptake. The arrow 34 indicates the direction of the draft leavingthe furnace-chamber opposed to the direction of the entering fuel. Inthe adaptation of my invention to this type of steamgenerator' thefurnace-door opening 10 is partially closed and fitted with a peep-holeSupplemental peep-holes are also. shown at 11 in the side walls of thechamber.

Thebase or floor of the 'cha1nber'is'com-. posed of a layer offire-brick 12 or other suitable device, supported upon ordinarygrategradually increased in the line of the the oil projected from theburner.

bars 13,' commonly used in boiler-furnaces.

As shown in-the plan view, Fig. 2, the floor or base is made practicallyair-tight for a greater portion of its area and is provided with aseries of openings 14 at the rear or lower part of the chamber anddirectly under the fuelburner 15. These opemngs are arranged to admitthe air in a suitable location with relationto the escape of the liquidfuel from the burner -15, the number of openings being path of being'toohighly heated by special The fuel-feeding apparatus with its connections and su ports and regulating-valves and'connected burner and theannular airinclosing space and distributing-openings leading to thefurnace-chamber are shown in Fig. 1 and in enlar ed parts in Figs. 3 and4. The liquid-fuel-de" steam and air pi arranged beneat suspended by thees 18 23 surrounding it are the floor of the furnace and grate-bearers27, as shown in Figs. 1 and 3. The steam-pipe 18 communicates with thesteam-space of the steamdrum 4 by the pipe 19, which is provided with astop-valve 20. The oil enters through the inner pipe 21, which isalsoprovided with a regulating-cock 22 and which is incased within pipe23 of larger diameter, which provides an air-jacket around the oil-pipe.tween the inlet-valves and 22 a branch connection or by-pass 24 isprovided, which is also provided with a stop-valve 25. v

The liquid-fueldelivery pipe 21, which, with the steam and air pipes 1823 surrounding it, constitutes the shank of the burner 15, is arrangedto ass from the front to the rear of the furnace elow the floor througha sheetiron. trough or slideway 26, which is suported by the regulargrate-bearersv 27,, the atter having appropriate 0 enings 28 providedfor this purpose, as shown in Fig. 4. The sheet-irontrou h grating 29toward t e rear, as shown in Fig. 3, so that the up ward'flow of the airfor combustion is not interrupted, while at the same time the burner issupported throughout its entire length and {can be guided into positionat the rear of the grating 29, where it is tulrned upward ninety degreesthrough the slot-like opening 30 in the brickwork, (shown in Fig. 2,).thus bringing the ti of the burner a few inches above the brick' oor ofthe furnace in such a way as to-blow the jet of mingled steam and oilin-a reverse'direction arallel .to the shank of'the burner. The va ves26 extends only to the,

ivery pipe 21 and the' Bee 20 and 22 for controlling the steamand oilare located at. the front of the furnace, at which point the operationof the burner is watched and controlled precisely the same as in theold-type settings. By disconnecting one on the oil and one two unions 31"and 32, on the steam pipe, the burner can be easily removed bywithdrawing it'through the sheetiron slideway 26. The burner shown givesa broadflat flame, the steam and oil being injected through parallelhorizontal slots 10-" cated in the tip. in its passage through the shankof the burner the oil is prevented from- Ineans of a pipe 23, whichseparates the oil-pipe 21 from the steam-space, thus providing anannular airjacket around the oil-pipe. This fuel-feeding apparatus andthe type of'burner shown is not erein claimed. It, however, fills the.requirements of the form of furnace and method of operation described.-and claimed.

In racticing the method herein described and c aimed I wish it tobeunderstood that said method is not intended to be limited in practicewith the kind of combustion-chamber shown and referred to as thepreferred form in the descriptive matter of the specification, as themethod of operation claimed can be effected in other forms of chamberwith the similar relative arrangement described of the exposedheating-surface with the path. of the projected fuel and itsdissemination by the effect of the furnace-draft, and whereby a forcedcombustion is permitted without injury to the heating-surface, which isan important feature of my invention.

It .will be observed that the gases between their entrance among thetubes and their exit therefrom pursue passes among the tubes separatedfrom each other by the deflectors 9 9. That portion of thefurnace-chamber 1 lying vertically beneath the first pass' correspondsin size and position withthe fire-box of the ordinary coal-burningboiler of this type.

That portion of the furnace-chamber which is not vertically beneath saidfirst pass (formed by movin the-bridge-wall 7 back from the positionwhich it ordinarily occupies under the forward deflector 9) constitutesa rearward extension of said fire-box and forms a fuel-chamber fromwhich the oil under ste ampressure is projected horizontally toward thefront of the furnace, and the air-openings in the bottom of whichfuel-chamber provide an upward draft of air beneath said projected fuel,which by the time the projected fuel has reached the fire-box proper orarea beneath the pass into the. tubes produces an upwardly-inclinedflame equably distributed over the area of said pass. This constructionenables the operator, looking in opposition to the projected fuelthrough the front peephole S and operating the steam and oil valvesadjacent thereto, to so regulate the fuel-supply as to providesufficient combustion for efliciency so equably distributed throughoutthe whole area of tubes exposed to the firebox as to induce the properwater circulation and without undue burning of tubes.

Having thus fully described a structure in-. volving my invention in theform at present preferred by me, what I claim, and desire to secure byLetters Patent, is-

1. In a water-tube-boiler furnace, means for atomizing oil andprojecting it into the furnace in the form of spray and in a direction 0posed to the draft leaving the furnacechamber above the roof thereofcombined" with Water-tubes in said roof.

2. In a water-tube-boiler furnace, means for atomizing oil andprojecting it into the furnace in the form of spray and in a directionsubstantially horizontal and opposed to the'draft leaving thefurnace-chamber above the roof thereof combined with water1\\bcs in saidroof. V

3. In a water-tube-boiler furnace, mean for atoinizing oil andprojecting it in the form of spray into a furnace-chamber of a sizeincreasing in the direction of the entering fuel combined with watertubes in the roof thereof.

4. In a water-tube-boiler furnace means for atomizing oil and projectingit in the form of spray into a furnace the roof of which l. upwardlyinclined in the direction of the entering fuel combined with water-tubesin the roof thereof.

5. In a water-tube-boiler furnace, means for atomizing oil andprojecting it in the fOIlH of spray into a furnace ofgradually-increasing size and in adirection opposed to the draft leavingthe furnace-chamber above the roof thereof combined with water-tubes insaid ronf.

6. In a watertubeboiler furnace inea H.\ for atomizing oil andprojecting it in the forir of spray into the furnace in a directionopposed to the draft leaving the furiiace-chaniber above the roofthereof combined with water-tubes in said roof and a floor provided withdraft-openings in thevicinity of the point where the atomized toolisintroduced and dead surfaces beyond the draft-openings.

7. In a water-tube-boiler furnace means for atomizing oil and projectingit in the form of spray into a furnace of gradually-increasing size in adirection substantially horizontal and opposed to the draft leaving thefurnace-chamber above the roof combined with water-tubes in said roofand a floor provided with draft-openings in the vicinity of the pointwhere the atomized fuel is introduced and dead surfaces beyond thedraft-openings.

8. In a water tubeboiler furnace, means for atomizing oil and projectingit in the form of spray into the furnace in a direction opposed to thedraft leaving furnace-chamber above the roof combined with watertubesforming a part of said roof and a dead surface in the roof in thevicinity of the point where the atomized fuel is introduced.

9.- In a water-tube-boiler furnace a combustion-chamber ofgradually-increasing size having a roof in part composed of water-tubesand in part of dead surfaces combined with means for introducing sprayedliquid fuel within the covered part of the chambers in a directionopposed to the draft leaving said chamber. a

10. In combination with a boiler-furnace, an atomizer provided withsupply-pipes enterin beneath the furnace-floor and extending fi om thefront to the rear of the furnace ioo under thefurnace-fioorsubstantially parallel with the path of the fuel discharged from theatomizer.

11. In combination with a boiler-furnace,

an atomizer provided with supply-pipes ex nace under tending from thefront to the rear of ti e fur- ;ported-by the beams which support saidfloor arches or and 0 said supply-pipes resting onsa1d guideway.

14.-The'combination with a steam-boiler of the horizontal inclinedwater-tube type having a projections closed at its bottom en to thewater-tubes at its top, of a fuel-c amber forming a rearward extension.of said fire-box, means whereby a hydrocarbon flame is projectedhorizontally from said fuel-chamber toward the front of said firebox andmeans for establishing a draft of air into saidfuel-chamber atsubstantially right angles to the course of the flame.

The combination with a steam-boiler of -t he horizontal inclinedWater-tube type I the gases having a plurality of passes for throughthe-tubes and a fire-box roofed by the-;--tubes in the first pass, -afuel-chamber forming a rearward extension of said fire-box supply-pipeseX- fire-box which is unobstructed by sasgrsse beneath the secondvpassmeans whereby .a hydrocarbon flame is fuel-chamber horizonta ly towardthe front rojected from said of the fire-box and means for establishinga i draft of air upward beneath said flame.

16. The combination with a steam-boiler of the horizontal water-tubetype. inclined upwardly toward the front having ;the entrance for thepassage of the gases at the up per end of said tubes and a fire-boxroofed by the tubes constituting a rearward extension from saidfire-box, means whereby a hydrocarbon flame is projected from saidfuel-chamber toward the front of said fire-box and means forestablishing a draft of air upward beneath said flame.

17. The combination with a steam-boiler having a fire-box which isunobstructed by arches or projections and closed at its bottom, of meansfor delivering a hyrdocarbon flame forwardly into the fire-box and meansfor establishing a draft of air same end of the firebox and atsubstantially right angles to the course of the flame.

In testimony whereof I have hereunto signed my'name in the presence oftwo 'subscribing witnesses.

' ERNEST H. PEABODY.

Witnesses:

i S. CHAS. YnAToN,

CHAS. RATHJEN.

into and at the u at saidentrance, of a fuel-chamber

